And finally tonight, a mystery. 1.2 million in cash had vanished. Fistfuls of hundred-dollar bills making safe passage to the federal reserve. How could anyone breach the security of the federal reserve? Dan harris has the details. It's on. Reporter: In movies like "ocean's eleven," the heists always have a certain panache. They're so ambitious. And they wear such great suits. Then there are those bold, caught on tape, smash and grab jobs we have seen, like the crooks who raided a mall in london on motorcycles. Or this $900,000 rolex robbery at a mall in atlanta this week. Look at it again. The thieves ll out hammers, grab the watches and then they're gone in seconds. But the heist involving swiss air flight 17 was much more stealthy and discreet. It involved three crates filled with $93 million in cash put in a shipping container and loaded onto the flight from zurich to new york's jfk airport. Somewhere along the way, somebody poked an arm-sized hole into one of the crates and grabbed 12 bundles of cash, each worth $100,000, all in $100 bills. Such modest foals. With 93 million bucks up for grabs, the robber -- or robbers -- snatched a mere $1.2 million. You think it's possible we have a thief with modest aims. 1.2 mill, that's enough for me. The small, unsophisticated thief is more than satisfied with that money. Reporter: Former nypd detective nick casale says that criminals involved in these high-profile heists. From the scene of a heist at jfk -- Reporter: Usually get caught. He says this one will get caught, too. He is going the get caught. Reporter: Enjoy your beer. We're always working for you at abcnews.Com. "Nightline" will be here later. See you back here tomorrow night.

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